RuntimeConfig: Unable to retrieve "text" value of the Variable

[mstal]

Description

The runtimeconfig.v1beta1.variable needs to be updated with "text" property so users will be able to access the text value.

Steps to reproduce with code samples

For creating the config with the name of my-config
gcloud beta runtime-config configs create my-config

For creating the key value pair, key is "some-gibberish" and value is "hahahablblblbl"
gcloud beta runtime-config configs variables set some-gibberish \
'hahahablblblbl' --config-name my-config

Now enter the Python command line by typing 'python' in the terminal and then hit enter.
Run following simple Python snippet

from google.cloud import runtimeconfig
client = runtimeconfig.Client()
config = client.config('my-config')
var = config.get_variable('some-gibberish')

Expected output:
>>> var.value

But what if we don't need the base64 encoding option given in the documentation?

So we're going to change this gcloud command to store the value of "some-gibberish" as text
gcloud beta runtime-config configs variables set some-gibberish \
'hahahablblblbl' --config-name my-config --is-text

Exit the python command line

Run the gcloud command with --is-text flag

Go to the python command line again, execute the simple Python snippet from earlier.

Output for var.value
>>> var.value
>>>

Output for var.text
>>> var.text
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'Variable' object has no attribute 'text'
>>>

Effect

For now this would mean that there's no way to retrieve the text values in Python which would force users to store everything as base64 encoded values.

[tseaver]

Per the API doc for variables, text is indeed an alternate to value as bytes.